ITV News said Ms Begum’s mother had received a letter from the Home Office on Tuesday.

The letter said Home Secretary Sajid Javid had ordered the move and it had already been processed.

It asked the mother to let her daughter know of the decision and to inform her she has a right to appeal.

Whitehall sources confirmed the home secretary had taken the decision. However, it is not clear on what grounds this was done.

Under the 1981 British Nationality Act someone can be deprived of their citizenship if the home secretary is satisfied that it would be “conducive to the public good” and they would not become stateless as a result.

Ms Begum said she travelled to Syria with her sister’s UK passport but it was taken from her when she crossed the border.

She is believed to be of Bangladeshi heritage but when asked by the BBC, she said did not have a Bangladesh passport and had never been to the country.

Image copyrightPA

Image caption
Ms Begum was 15 and living in Bethnal Green, London, when she left the UK in 2015

Mr Javid told MPs on Monday he would not “hesitate to prevent” the return of Britons who travelled to Syria to join IS.

He said more than 100 dual nationals have already lost their UK citizenship after travelling in support of terrorist groups.